The proposed work is designed to elucidate RNA metabolism as it is related to growth, development and function of both normal and neoplastic cells. Emphasis will be placed on the stydy of RNA polymerase III (C) (ribonucleosde triphosphate: RNA nucleotidyl-transterase (EC 2.7.7.6.)), on of the three major eukaryotic RNA polymerases. This polymerase has been shown to be responsible for the synthesis of 5S RNA, tRNA and 5.5S adenovirus associated RNA. Using enzyme purified from calf thymus and bovine lymphosarcoma RNA synthesis will be studied using both DNA and chromatin templates. In vitro studies utilizing purified enzyme and template should furnish an insight into the relative roles of polymerase and the various components of chromatin in determining the specific transcription which occurs in vivo. Emphasis will be placed on transcription of the 5S genome using a cDNA copy of 5S RNA, which has been obtained enzymically. In addition, transcription of tRNA and 5.5S adenovirus associated RNA will be studied.